John p



UNITED STATES PATENT OFFICE.

JOHN P. SHERVOOD, OF FORT EDWARD, NEW YORK.

' LocK.

Specification of Letters Patent No'.

To all whom t may concern:

Be it known that I, JOHN P. SHERwooD, of Fort Edward, in the county of Washing ton and State of New York, have invented a new and Improved Door-Lock; and I do hereby declare that the following is a full and exact description thereof, reference being had to the accompanying drawings,

v' making a part of this specification, Figures 1 and 2 being views of the interior portion of t-he lock; Fig. 3, a view of the same after the tumbler B has been removed; Figs. 4 and 5, edge views of the bolt A and tumbler B detached from the lock, and Fig. 6 a section in the line 'y y of Fig. 1.

Similar letters indicate like parts in each drawing.

My invention consists in giving the bolt A, and the tumbler B, of a lock such a shape, that when the tumbler B, is in its normal position, the spring e, will project the bolt A, a suiicient distance for latching purposes and enable it to be readily thrown back again by the knob-shank; and when the outer ends of the legs of said tumbler are thrown either up or down by the key a sufficient distance to det-ach them from the teeth y', j, on the side of the bolt, the spring e, will further project the bolt outward into the' locking position shown in Fig. 1, and

beyond t-he reach of the arms i, z', on the knob-shank-follower la; and the moment that the key is turned a suficient distance in the lock the spring f, will throw the tumbler into its normal posit-ion again, when the teeth b, which project from the under side of the extremities of the legs of said tumbler, willactagainst the inner sides of the teeth j, y', on the side of the bolt, and prevent said bolt from being withdrawn until the tumber is again vibrated by the key.

The key-hole is of such a shape that the key may be inserted ,into it either side up. When the key is t-urned in the lock, it irst strikes against one of the legs of the tumbler B, and vibrates the tumbler to such a degree as to throw its teeth b, clear of the teeth 7', j, on the bolt, and the instant that this is accomplished, the key strikes against one of t-he projections m, from the inner edge of one of the legs a, of the bolt, and throws back said bolt into the position shown in Fig 2; at which moment the key ceases to act upon the tumbler and allows it to spring back into its normal position-shown in Fig. Q-when it will keep the said bolt in its 18,162, dated September 8', 1857.

latching position and within reach of the legs z', 2'-, in the knob-shank-follower h, until it is again vibrated by the key.

The tumbler B, works upon a tubular pivot d, which projects from t-he back of the lock case. A shank n, which has a rightangular arm at its inner end, is inserted within the tubular pivot cl, and is drawn cut-ward by means of the spring o. A notch p, is formed in the left-hand side of the aperture in the tumbler, and a notch of corresponding width is formed in one side of the inner end of the tubular pivot cl. When the tumbler is in the normal position represented in Figs. 1, and 2, the said notches in the tumbler and in the inner end of the pivot d, are exactly opposite each other. And when the tumbler is in this position, by taking hold of the knob on the outer end of the shank n, and turning it to the proper position, the right angular arms on the inner end of said shank will be drawn into the aforesaid notches in the tumbler and the tubular pivot, and will retain the tumbler in said positio-n until the shank is forced inward and turned to the right or left a suicient distance to carry the retaining arm on its inner end beyond the reach of said notches. When the said tumbler is thus secured in its normal posit-ion, the key cannot be turned within the lock for the purpose of throwing the bolt into a locked position, nor for the purpose of unlocking the said bolt after it has been thrown into a locked posit-ion.

l/Vhat I claim as my invention and desire to secure by Letters Patent, is-

1. The improvement in locks produced by so shaping and arranging the bolt A, and the tumbler B, of a lock that the said tumbler is enabled to retain the bolt within reach of the arms a', z', on the knob-shankfollower, when it is used as a spring-latchbolt, and also retain t-he said bolt in a position beyond the reach of said arms, when it is thrown outward, by the key, into a position to serve as a lock-bolt, substantially as herein set forth. V

2. I do not claim the use of a dead-latch operating directly on the locking bolt to prevent it from being locked or unlocked by the key, as that device is well known, but I do claim as the second feature of my invention, the combination o-f the lever-shank n, with the tubular pivot d, and the tumbler B, in such a manner that it may be made to firmly look the tumbler n such a position as to p1roteot the bolt fron any action of the key and thereby prevent the looking or unlock-vk ing of the bolt in the manner substantially as herein set forth.

The above speefloaton of my new and useful improvement in door locks, signed andWtnessed this eighth day of J une A. D. 185

J. P. SHERVOOD. 

